Game system for varying parameter of a character

ABSTRACT

A game apparatus generates a game image for display on a display screen. A size and a shape of an attack input supplied to the game apparatus is determined and one or more characteristics of an attacked game character is changed based on one or both of the size and shape of the supplied attack input.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of application Ser. No. 10/879,071,filed Jun. 30, 2004.

BACKGROUND AND SUMMARY

Conventionally, there have been proposed game apparatuses which can beoperated using an input device other than a controller having across-key pad and buttons. For example, there is a conventional gamesystem for playing a game using a sword-like controller to attack enemycharacters in the game. In this game system, a position of thesword-like controller and an amount of variation in the position perunit of time are detected by a sensor, and a degree of damage caused toan enemy character by attack is determined in accordance with the speedor amplitude of swing of the sword-like controller. In such aconventional game system, the player is able to feel as if he/she isattacking the enemy characters in the game using a real sword.

In the above conventional game system, the degree of damage caused to anenemy character is determined in accordance with the speed or amplitudeof swing of the sword-like controller, and the means of attacking theenemy characters is limited to a sword, lacking variation in attack.Such simple means of attacking makes the game itself monotonous, easilyboring the player.

Specifically, one input operation uniquely makes one type of attackaction, and therefore the game easily bores the player. It is importantin particular for new games to enable a variety of types of attacksincluding, for example, not only a direct attack by a sword but also anattack by magic, and also to enable a damage degree and an area affectedby an attack to be designated, thereby keeping the player from becomingbored with the game.

Therefore, an aspect of an exemplary illustrative embodiment is a gamesystem which enables various game operations to provide a player with anopportunity to play a game in various manners.

The exemplary illustrative embodiments herein have the followingfeatures to attain the aspect mentioned above. It should be noted thatreference numerals and supplemental remarks in parentheses merelyindicate correspondence with a preferred embodiment which will bedescribed further below for the purpose of better understanding of theexemplary illustrative embodiments, and do not restrict the scope of thepresent invention.

A first aspect of an exemplary illustrative embodiment is directed to acomputer-readable storage medium having a game program stored therein,the game program causing a computer of a game apparatus (1), whichincludes a display screen (a first LCD 11) for displaying a game imageand a touch panel (13) provided on the display screen, to implement amethod comprising: a game image display control step (a CPU core 21implementing steps S41; hereinafter, only step numbers are shown); acoordinate detection step (S53); a shape identification step (S64); asize calculation step (S66); a basic condition determination step (S65);an effectiveness determination step (S67); and a characteristicparameter change step (S77). The game image display control step allowsa game image comprising one or more game characters (enemy characters 31and 32) to be displayed on the display screen. The coordinate detectionstep detects a coordinate value at predetermined time intervals, thecoordinate value indicating a position on the touch panel where aplayer's input is provided. The shape identification step identifies agraphical shape of an input trajectory represented by a coordinate valuegroup (an input coordinate list 22 a) detected by the coordinatedetection step. The size calculation step calculates a size of thegraphical shape of the input trajectory represented by the coordinatevalue group detected by the coordinate detection step. The basiccondition determination step determines a basic condition (an attackstyle) for changing a characteristic parameter (HP or MP of an enemycharacter), which indicates a characteristic of a game character, basedon the graphical shape identified by the shape identification step. Theeffectiveness determination step determines an effectiveness of thebasic condition for the game character based on the size calculated bythe size calculating step. The characteristic parameter change stepchanges the characteristic parameter of the game character based on thebasic condition determined by the condition determination step and theeffectiveness determined by the effectiveness determination step.

Further, the method may further comprise a character selection step(S71). The character selection step selects at least one game characterhaving a character parameter to be changed, from among the one or moregame characters comprising the game image. In this case, thecharacteristic parameter change step changes only the characteristicparameter of the at least one game character selected by the characterselection step.

A second aspect of an exemplary illustrative embodiment is directed to acomputer-readable storage medium having a game program stored therein,the game program causing a computer of a game apparatus (1), whichincludes a display screen for displaying a game image and a touch panel(13) provided on the display screen (a first LCD 11), to implement amethod comprising: a game image display control step (S41); a coordinatedetection step (S53); a shape identification step (S64); a characterselection step (S71); a basic condition determination step (S65); and acharacteristic parameter change step (S77). The game image displaycontrol step allows a game image comprising game characters (enemycharacters 31 and 32) to be displayed on the display screen. Thecoordinate detection step detects a coordinate value at predeterminedtime intervals, the coordinate value indicating a position on the touchpanel where a player's input is provided. The shape identification stepidentifies a graphical shape of an input trajectory represented by acoordinate value group (an input coordinate list 22 a) detected by thecoordinate detection step. The character selection step selects at leastone game character having a characteristic parameter (HP or MP of anenemy character), which indicates a characteristic of the game characterand is required to be changed, from among the game characters comprisingthe game image based on an area on the display screen which is definedby the input trajectory. The basic condition determination stepdetermines a basic condition (e.g. an attach style) for changing thecharacteristic parameter, which indicates the characteristic of the gamecharacter, based on the graphical shape identified by the shapeidentification step. The characteristic parameter change step changesthe characteristic parameter of the at least one game character selectedby the character selection step, based on the basic condition determinedby the condition determination step.

Further, the method may further comprise a size calculation step (S66)and an effectiveness determination step (S67). The size calculation stepcalculates a size of the graphical shape of the input trajectoryrepresented by the coordinate value group detected by the coordinatedetection step. The effectiveness determination step determines aneffectiveness of the basic condition for the at least one game characterbased on the size calculated by the size calculating step. In this case,the characteristic parameter change step changes the characteristicparameter of the at least one game character based on the effectivenessof the basic condition determined by the effectiveness determinationstep.

Furthermore, the characteristic parameter change step may change adegree of change in the characteristic parameter in accordance with anumber of the at least one game character selected by the characterselection step.

Further still, the method may further comprise a change representationaddition step (S76). The change representation addition step changes thegame image in a different manner in accordance with a type of the basiccondition determined by the graphical shape of the input trajectoryafter the graphical shape of the input trajectory is identified by theshape identification step.

Further still, the method may further comprise a trajectory displaycontrol step (S56). The trajectory display control step displays theinput trajectory in a position on the display screen which correspondsto the coordinate value detected by the coordinate detection step.

Further still, a plurality of pieces of reference graphics dataindicating types of the basic condition and predetermined shapes may bestored in the game apparatus. In this case, the shape identificationstep selects a piece of reference graphics data, which indicates a shapemost analogous to a shape represented by the coordinate value group,from among the plurality of pieces of reference graphics data stored inthe game apparatus, and then the shape identification step determinesthe shape represented by the selected piece of reference graphics dataas the graphical shape of the input trajectory.

Further still, the method may further comprise a vector data groupcalculation step and a correction step. The vector data groupcalculation step calculates a vector data group (a vector data list 22b) indicating a distance and a direction between sequential coordinatevalues based on the coordinate value group detected by the coordinatedetection step. The correction step corrects a plurality of sequentialpieces of vector data indicating a same direction and included in thevector data group, so as to be represented as a piece of vector data. Inthis case, the shape identification step selects a piece of referencegraphics data indicating a shape most analogous to a shape of the vectordata group (input trajectory data 22 c) corrected by the correctionstep.

Note that an exemplary embodiment also provides a game apparatuscomprising: a storage medium (a WRAM 22 or a cartridge (17) having theabove game program stored therein; and a program implementing section (aCPU core 21) for implementing the game program stored in the storagemedium.

In the first aspect, two elements, which comprise a basic condition forchanging (increasing/decreasing) a characteristic parameter of a gamecharacter and an effectiveness of the basic condition, are determinedbased on a graphical shape and a size of an input trajectory provided inone input operation by the user. Accordingly, it is possible to makemore diverse changes to the characteristic parameter by a simpler inputoperation. Moreover, the graphical shape is directly inputted via atouch panel on which the game character is displayed, and therefore itis possible for the user to more intuitively perform an input operationwith higher accuracy. Note that the basic condition as described hereincorresponds to, for example, the type of magic for attacking an enemycharacter, the type of attack other than the magic, an attack styleincluding a combination of magic and an attack other than the magic, orthe type of magic for recovering the player character's power. Thus, forexample, in a battle game of attacking enemy characters, it is possibleto realize more diverse attack styles based on the first aspect. Thatis, in the first aspect, various game operations are realized, wherebyit is possible to provide a player with an opportunity to play a game invarious manners. Moreover, it is possible to provide a game which allowsthe user to experience a feeling of operation which is intuitive and notmonotonous compared to, particularly, a game system for use with a gamewith command input-type battle scenes.

In the case where the method further includes the character selectionstep, not all game characters displayed on the display screen areconsidered to have a character parameter to be changed, and a gamecharacter/game characters having a character parameter to be changedis/are determined by an area defined by an input trajectory on thedisplay screen. That is, the game character/game characters having acharacter parameter to be changed is/are changed in accordance with aninput position on the touch panel, and therefore more diverse gameprocesses are provided in accordance with input operations, therebymaking the game more enjoyable.

In the second aspect, two elements, which comprise a game characterhaving a characteristic parameter to be changed and a basic conditionfor changing (increasing/decreasing) the characteristic parameter, aredetermined based on a graphical shape and a position of an inputtrajectory provided in one input operation by the user. Accordingly, itis possible to make more diverse changes to the characteristic parameterby a simpler input operation. Thus, in the second aspect, as in thefirst embodiment, for example, in a battle game of attacking enemycharacters, it is possible to realize more diverse attack styles inaccordance with diverse input operations via the touch panel. That is,in the second aspect, various game operations are realized, whereby itis possible to provide a player with an opportunity to play a game invarious manners so as not to bore the user.

In the case where a degree of change in the characteristic parameter ischanged in accordance with the number of game characters selected by thecharacter selection step, the degree of the characteristic parameter ischanged in accordance with not only the shape of the input trajectory,etc., but also the position of the game character on the display.Accordingly, the game unfolds differently each time the player performsthe same input operation. Thus, it is possible to provide a player withan opportunity to play the game in various manners. Moreover, the playeris required to pay attention to the position of the game character onthe display screen, while performing the input operation, making thegame more complex and difficult to play. Thus, it is possible to providea game which is not monotonous and/or boring to the player.

Further, in the case where the method further includes the changerepresentation addition step, it is possible to provide the player witha visual effect which varies in accordance with the basic condition,thereby making the game more enjoyable. That is, it is possible topresent to the player a change of a game image in accordance with thegraphical shape of the input trajectory. Moreover, the player is able tovisually and intuitively know how the player him/herself is performingan input operation. Accordingly, the player is able to readily knowwhether the input operation is performed in a desired manner.

Furthermore, in the case where the method further includes thetrajectory display control step, a result of the player's inputoperation is displayed on the display screen. Accordingly, the player isable to readily know how the player him/herself is performing an inputoperation. Thus, the player is able to readily know whether the inputoperation is performed in a desired manner.

Further still, in the case where a plurality of pieces of referencegraphics data are stored in the game apparatus, it is possible toreadily identify a graphical shape of the input trajectory.

Further still, in the case where the method further includes the vectordata group calculation step and the correction step, the shape of atrajectory drawn on the touch panel by the player is simplified by thecorrection step. Accordingly, it is possible to simplify a process forcomparing the vector data group to the reference graphics data, therebyincreasing the processing speed, while reducing a processing load on thecomputer.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages will be better and morecompletely understood by reference to the following detailed descriptionof exemplary illustrative embodiments in conjunction with the drawingsof which:

FIG. 1 is an external view of a portable game apparatus according to anexemplary illustrative embodiment;

FIG. 2 is a block diagram showing an internal structure of a gameapparatus 1;

FIG. 3A is a diagram showing an exemplary game image displayed on adisplay screen of a first LCD 11;

FIG. 3B is a diagram showing another exemplary game image displayed onthe display screen of the first LCD 11;

FIG. 4A is a diagram showing an exemplary game image displayed when aplayer is performing an attack operation;

FIG. 4B is a diagram showing another exemplary game image displayed whenthe player is performing an attack operation;

FIG. 5 is a diagram showing an exemplary game image where an inputtrajectory has a triangular shape;

FIG. 6 is a diagram showing an exemplary game image where the inputtrajectory has a rectangular shape;

FIG. 7A is a diagram showing an exemplary game image where a pluralityof enemy characters are attacked;

FIG. 7B is a diagram showing another exemplary game image where aplurality of enemy characters are attacked;

FIG. 8A is a diagram showing an exemplary game image displayed after theplayer's attack operation;

FIG. 8B is a diagram showing another exemplary game image displayedafter the player's attack operation;

FIG. 9 is a diagram showing a memory map of a WRAM 22 included in thegame apparatus 1;

FIG. 10 is a flowchart showing a flow of a game process implemented bythe game apparatus 1;

FIG. 11 is a flowchart showing a detailed flow of a process of step S44shown in FIG. 10;

FIG. 12 is a diagram schematically showing how an input to a touch panelis performed;

FIG. 13 is a diagram showing an exemplary input coordinate list 22 a;

FIG. 14 is a flowchart showing a detailed flow of a process of step S45shown in FIG. 10;

FIG. 15A is a diagram used for explaining a process for simplifying theinput coordinate list 22 a;

FIG. 15B is another diagram used for explaining the process forsimplifying the input coordinate list 22 a;

FIG. 15C is still another diagram used for explaining the process forsimplifying the input coordinate list 22 a;

FIG. 16A is still another diagram used for explaining the process forsimplifying the input coordinate list 22 a;

FIG. 16B is still another diagram used for explaining the process forsimplifying the input coordinate list 22 a;

FIG. 17A is a diagram used for explaining a vector data list 22 b;

FIG. 17B is another diagram used for explaining the vector data list 22b;

FIG. 18 is a diagram showing an example of input trajectory data 22 c;

FIG. 19 is a diagram showing an example of a reference graphics database22 d;

FIG. 20 shows an exemplary attack determination table;

FIG. 21 is a flow chart showing a detailed flow of a process of step S46shown in FIG. 10;

FIG. 22 is a diagram showing an example of enemy character status data;

FIG. 23 is a diagram showing an exemplary game image where an inputtrajectory has an arc shape;

FIG. 24 is a diagram showing an exemplary game image where an inputtrajectory has a spiral shape;

FIG. 25 is a diagram showing an exemplary game image where an inputtrajectory has an undulating shape;

FIG. 26 is a diagram showing an exemplary game image where an inputtrajectory has a shape which cannot be drawn with one stroke;

FIG. 27 shows a variation of a portable game apparatus;

FIG. 28 shows another variation of the portable game apparatus; and

FIG. 29 shows still another variation of the portable game apparatus.

DETAILED DESCRIPTION

FIG. 1 is an external view of a portable game apparatus according to anexemplary illustrative embodiment. In FIG. 1, a game apparatus 1includes two liquid crystal displays (LCDS) 11 and 12 which areaccommodated in a housing 18 so as to establish a predeterminedpositional relationship therebetween. Specifically, in order toaccommodate the first and second LCDs 11 and 12 in a vertical direction,the housing 18 includes a lower housing 18 a and an upper housing 18 b.The upper housing 18 b is supported on a portion of an upper sidesurface of the lower housing 18 a so as to be freely flipped about thatportion of the upper side surface of the lower housing 18 a. The upperhousing 18 b has a planar shape slightly larger than the second LCD 12,and a top surface of the upper housing 18 b has an opening to expose adisplay screen of the second LCD 12. The lower housing 18 a has a planarshape wider than the upper housing 18 b, and a top surface of the lowerhousing 18 a has an opening substantially formed in its center so as toexpose a display screen of the first LCD 11. The lower housing 18 a hassound holes 15 a for a loudspeaker 15 provided on one of two sidesopposed to each other with respect to the first LCD 11, and also haselements of an operating switch section 14 provided on either one of thetwo sides.

Specifically, the operating switch section 14 includes operationswitches 14 a and 14 b, a cross direction keypad 14 c; a start switch 14d, and a select switch 14 e. The operation switches 14 a and 14 b areprovided on the top surface of the lower housing 18 a so as to belocated to the right of the first LCD 11. The cross direction key pad 14c, the start switch 14 d, and the select switch 14 e are provided on thetop surface of the lower housing 18 a so as to be located to the left ofthe first LCD 11. The operation switches 14 a and 14 b are used forinputting instructions to jump, punch, operate a weapon, and so on in anaction game, or inputting instructions to obtain an item, select anddetermine a weapon or a command, and so on in a role playing game (RPG)such as a simulation RPG. The cross direction keypad 14 c is used forindicating a moving direction on a game screen, e.g., a direction tomove a player object (or a player character) which can be operated bythe player, or a direction to move a cursor. If necessary, additionaloperation switches may be provided, or side switches 14 f and 14 g maybe provided respectively on right and left sides of the upper sidesurface of the lower housing 18 a as shown in FIG. 1.

Further, a touch panel 13 is provided on the first LCD 11 (as indicatedby broken lines in FIG. 1). For example, the touch panel 13 may be of aresistive film type, an optical type (e.g. an infrared type), or acapacitive coupling type. When a stick 16 (or a finger) presses,strokes, or moves on the touch panel 13, the touch panel 13 detects acoordinate position of the stick 16 and outputs coordinate data.

The upper housing 18 b has a storage hole 15 b (indicated by two-dotdashed lines in FIG. 1) formed in the vicinity of a side surface thereofin order to store the stick 16 for operating the touch panel 13 asnecessary. The lower housing 18 a has a cartridge insertion portion(indicated by one-dot dashed lines in FIG. 1) in a side surface thereofin order to freely load/unload a game cartridge 17. The cartridge 17includes an information storage medium, e.g., a nonvolatilesemiconductor memory such as a ROM or a flash memory, and has a gameprogram recorded in the information storage medium. The cartridgeinsertion portion includes a connector (see FIG. 2) for electricallyconnecting the cartridge 17 to the game apparatus 1. The lower housing18 a (or the upper housing 18 b) accommodates an electronic circuitboard having mounted thereon various electronics including a CPU. Notethat the information storage medium having a game program stored thereinis not limited to the nonvolatile semiconductor memory, and may be anoptical disk such as a CD-ROM or a DVD.

An internal structure of the game apparatus 1 is described now withreference to FIG. 2. FIG. 2 is a block diagram showing the internalstructure of the game apparatus 1.

In FIG. 2, the electronic circuit board accommodated in the housing 18 ahas a CPU core 21 mounted thereon. The CPU core 21 is connected througha predetermined path to a connector 28 for connection to the cartridge17, and also connected to an input and output interface (I/F) circuit27, a first graphics processing unit (GPU) 24, a second GPU 26, and aworking RAM (WRAM) 22.

The cartridge 17 is detachably connected to the connector 28. Asdescribed above, the cartridge 17 is a storage medium having a gameprogram stored therein, and specifically includes a ROM 171 in which thegame program is stored and a RAM 172 for storing backup data in arewritable manner. The game program stored in the ROM 171 of thecartridge 17 is loaded to the WRAM 22, and then implemented by the CPUcore 21. The WRAM 22 stores temporary data obtained by the CPU core 21implementing the game program or data for generating images.

The I/F circuit 27 is connected to the touch panel 13, the operatingswitch section 14, and the loudspeaker 15. The loudspeaker 15 is locatedbehind a portion of the lower housing 18 a where the sound holes 15 bare formed.

The first GPU 24 is connected to a first video RAM (VRAM) 23, and thesecond GPU 26 is connected to a second VRAM 25. The first GPU 24,responsive to an instruction from the CPU core 21, generates a firstgame image based on data for generating an image stored in the WRAM 22,and renders the generated image on the first VRAM 23. The second GPU 26,responsive to an instruction from the CPU core 21, generates a secondgame image based on data for generating an image stored in the WRAM 22,and renders the generated image on the second VRAM 25.

The first VRAM 23 is connected to the first LCD 11, and the second VRAM25 is connected to the second LCD 12. The first GPU 24 outputs the firstgame image rendered on the first VRAM 23 to the first LCD 11. The firstLCD 11 displays the first game image outputted from the first GPU 24.The second GPU 26 outputs the second game image rendered on the secondVRAM 25 to the second LCD 12. The second LCD 12 displays the second gameimage outputted from the second GPU 26.

Described next is a game process implemented by the game apparatus 1 inaccordance with the game program stored in the cartridge 17. Note thatin an exemplary illustrative embodiment, a game image is displayed onlyon the first LCD 11 having the touch panel 13 provided on its displayscreen. Accordingly, the game apparatus of such exemplary illustrativeembodiments may be configured so as not to include the second LCD 12.The game apparatus of the exemplary illustrative embodiments herein canbe realized by a game apparatus, a PDA, or the like, which includes atleast one display device and implements a game program according to anexemplary illustrative embodiment.

The game process implemented by the game apparatus 1 is described firstalong with an outline of a game implemented by the game apparatus 1.FIGS. 3A and 3B each show an exemplary game image displayed on thedisplay screen of the first LCD 11.

The present exemplary illustrative embodiment is described by taking asan example a role-playing game as shown in FIG. 3A, though games of anytype can be implemented by the game apparatus of the present invention.Scenes in the role playing game are generally classified into two types:a movement scene (FIG. 3A) in which a player character operated by theplayer moves on a game map, and a battle scene (FIG. 3B) in which theplayer character fights against enemy characters. In the movement scene,if a predetermined condition for the player character to encounter anenemy character is satisfied, the label “ENEMY APPEARED!!” is displayedas shown in FIG. 3A, and thereafter the game image is switched to thebattle scene as shown in FIG. 3B. In the battle scene, the enemycharacter and characteristic parameters of the player character and theenemy character are displayed. In FIG. 3B, two enemy characters 31 and32 are displayed. Note that each characteristic parameter indicates avalue representing a characteristic of a game character appearing in thegame. Specifically, the characteristic parameter is displayed on thefirst LCD 11 to indicate the player character's hit points (HP) or magicpoints (MP), or an enemy character's HP or MP. After the game image isswitched to the battle scene, a battle progresses as the playercharacter and the enemy characters attack each other.

FIGS. 4A and 4B each show an exemplary game image displayed when theplayer is performing an attack operation. When the player character'sturn to attack comes during a battle, the player performs the attachoperation using the touch panel 13. As shown in FIG. 4A, the playermoves a finger (or the stick 16) on the touch panel 13. In this case,the player moves the finger so as to draw a predetermined trajectory (areference graphic as described below). Such a trajectory indicates aposition on the touch panel 13 where the player's input is provided, andis hereinafter referred to as an “input trajectory”. For example, theshape of the input trajectory is predetermined to be circular,triangular, or rectangular. Accordingly, the player moves the finger onthe touch panel 13 so as to draw, for example, a triangular orrectangular input trajectory. Note that in FIG. 4A, the one-dot chainlines indicate the movement of the player's finger.

The game image includes an input trajectory representation 33representing the input trajectory (e.g., the broken line of FIG. 4A).The input trajectory is displayed at a position on the display whichcorresponds to a position on the touch panel 13 where the player's inputis provided. That is, the input trajectory representation 33 isdisplayed as the player's finger moves on the touch panel 13. In FIG.4A, the input trajectory is represented by a circle-like shape. Theinput trajectory representation 33 allows the player to clearly anddirectly perceive the input trajectory drawn by his/her input operation.Accordingly, the player is able to know whether the input trajectory isdrawn in a desired shape.

The exemplary game image of FIG. 4B is displayed after the player'sattack operation. In the present exemplary illustrative embodiment, theplayer character attacks an enemy character present in an area enclosedby the input trajectory. Accordingly, in FIG. 4B, an enemy character 31is damaged by an attack of the player character. In the case where thereis no enemy character in the area enclosed by the input trajectory, theplayer character is deemed to fail in the attack. If the playercharacter is successful in the attack, an effect representation 34 isdisplayed for representing the player character's attack against theenemy character 31. Further, a damage indication 35 is displayed toindicate a degree of damage caused to the enemy character 31 by theplayer character's attack. At this point, the game apparatus 1 changesthe characteristic parameter HP of the enemy character 31. In theexample of FIG. 4B, the HP of the enemy character 31 is decreased by 90.

Note that in FIG. 4A, it is preferred that the enemy character 31 and anenemy character 32 move within a displayed area. This is becausemovements of the enemy characters 31 and 32 targeted for attack (e.g.targeted to be enclosed by the input trajectory) make it difficult toenclose the targeted enemy characters 31 and 32 by themselves with theinput trajectory, thereby making the game more enjoyable.

In the present exemplary illustrative embodiment, the style of attack bythe player character is changed in accordance with the shape of theinput trajectory. Examples of the style of attack by the playercharacter include an attack by a sword and an attack by magic. Moreover,there are different types of attacks by magic, such as an attack by firemagic and an attack by water magic. FIG. 5 shows an exemplary game imagewhere the input trajectory is triangular. In the present exemplaryillustrative embodiment, when the player performs an input operation soas to draw a triangular input trajectory, the player character attemptsan attack by wind magic. Note that in FIG. 5, the enemy character 31 islocated outside the area enclosed by the triangular input trajectory,and therefore the player character fails in the attack. FIG. 6 shows anexemplary game image where the input trajectory is rectangular. In thepresent exemplary illustrative embodiment, when the player performs aninput operation so as to draw a rectangular input trajectory, the playercharacter attempts an attack by water magic. Note that when the playerperforms an input operation so as to draw a circular input trajectory(see FIG. 4A), the player character attempts an attack by fire magic. Asdescribed above, in the present exemplary illustrative embodiment, thestyle of attack is changed in accordance with the shape of the inputtrajectory. Accordingly, the player is able to provide diverse attacksby drawing input trajectories of various shapes on the touch panel 13.

Further, in the present exemplary illustrative embodiment, a degree ofdamage to be caused to an enemy character varies in accordance with thesize of the input trajectory. FIGS. 7A and 7B each show an exemplarygame image in the case of attacking a plurality of enemy characters.Specifically, an exemplary game image displayed when the player isperforming an attack operation is shown in FIG. 7A. In FIG. 7A, theinput trajectory is larger in size than the input trajectory shown inFIG. 4A. Note that in FIG. 7A, two enemy characters 31 and 32 areenclosed by the input trajectory, and therefore targeted for attack bythe player character. An exemplary game image displayed after theplayer's attack operation is shown in FIG. 7B. In FIG. 7B, a degree ofdamage caused to an enemy character is different from the degree ofdamage shown in FIG. 4B. Specifically, in FIG. 7B, the degree of damagecaused to an enemy character is less than the degree of damage shown inFIG. 4B. In this manner, in the present exemplary illustrativeembodiment, the degree of damage to be caused to an enemy character byan attack decreases as the size of the input trajectory increases.

Furthermore, in the present exemplary illustrative embodiment, the typeof the effect representation 34 varies in accordance with the style ofthe player character's attack. FIGS. 8A and 8B each show an exemplarygame image displayed after the player's attack operation. Specifically,an exemplary game image of FIG. 8A is displayed after the playercharacter's attack by fire magic. In FIG. 8A, an effect representation34 a, which represents that the enemy character 31 is attacked by fire,is displayed on the display screen of the first LCD 11. An exemplarygame image of FIG. 8B is displayed after the player character's attackby a sword. In FIG. 8B, an effect representation 34 b, which representsthat the enemy character 31 is slashed with a sword, is displayed on thedisplay screen of the first LCD 11. In this manner, the effectrepresentation is changed in accordance with the style of attack, andtherefore the player is able to visually perceive what kind of attack isattempted by his/her input operation. Accordingly, the player is able tovisually confirm whether his/her input operation results in a desiredattack.

Next, the details of the game process implemented by the game apparatus1 are described. Described first is data that is stored into the WRAM 22during the game process. FIG. 9 is a diagram showing a memory map of theWRAM 22 included in the game apparatus 1. For example, an inputcoordinate list 22 a, a vector data list 22 b, input trajectory data 22c, a reference graphics database 22 d, a damage determination table 22e, and enemy character status data 22 f are stored into the WRAM 22during the game process. In addition to the above, a game program andgame image data read from the cartridge 17 are stored in the WRAM 22.

The input coordinate list 22 a comprises a set of coordinate values (acoordinate value group). Each coordinate value indicates a position onthe touch panel where the player's input is provided. In the presentexemplary illustrative embodiment, positions on the touch panel wherethe player's input is provided are detected at prescribed timeintervals. While the player continuously provides inputs (for example,while the player's finger remains on the touch panel), coordinatevalues, which indicate detected positions, are stored as a list in theWRAM 22.

The vector data list 22 b comprises a set of vector data (a vector datagroup). Each piece of vector data in the set indicates a direction and adistance between adjacent coordinate values comprising the inputcoordinate list 22 a. The vector data list 22 b is obtained based on theinput coordinate list 22 a.

The input trajectory data 22 c represents, as a piece of vector data, aplurality of sequential pieces of vector data indicating the samedirection and comprising the vector data list 22 b. Accordingly, theinput trajectory data 22 c is obtained based on the vector data list 22b.

The reference graphics database 22 d comprises a plurality of pieces ofreference graphics data. Each piece of the reference graphics datarepresents a reference graphic designed so as to be associated with astyle of attack by the player character, and the number of the pluralityof pieces of the reference graphics data corresponds to the number ofstyles of attack by the player character. Note that the referencegraphics database 22 d is typically stored in the cartridge 17 togetherwith the game program, and read from the cartridge 17 onto the WRAM 22at the beginning of the game process. In the present exemplaryillustrative embodiment, similar to the vector data list 22 b and theinput trajectory data 22 c, the reference graphics data comprises aplurality of pieces of vector data. Note that the following descriptionsof the game process are provided on the assumption that the referencegraphics database 22 d comprises reference graphics data representing acircle associated with an attack by fire magic, reference graphics datarepresenting a triangle associated with an attack by wind magic, andreference graphics data representing a rectangle associated with anattack by water magic.

The damage determination table 22 e is used for determining a degree ofdamage caused to an enemy character targeted for attack based on thestyle of an attack, the size of an input trajectory, and an attribute ofthe enemy character. Note that the size of the input trajectorycorresponds to the size of a graphic drawn by the input trajectory, andthe attribute of the enemy character is a parameter indicating a degreeof resistance to the style of a specific attack. For example, theattribute of the enemy character indicates that the enemy character hashigh resistance to an attack by fire magic or low resistance to anattack by wind magic. Specifically, examples of the attribute include awater attribute, a fire attribute, etc. An enemy character having thewater attribute has low resistance to an attack by fire magic but hashigh resistance to an attack by water magic. An enemy character having afire attribute has low resistance to an attack by water magic but hashigh resistance to an attack by fire magic.

The enemy character status data 22 f indicates the status of the enemycharacter. In the present exemplary illustrative embodiment, the enemycharacter status data 22 f comprises characteristic parameters HP and MPof the enemy character, as well as data indicating attributes of theenemy character as described above. If the enemy character is attackedby the player character, the enemy character's HP stored in the WRAM 22is reduced. If the enemy character's HP is reduced to zero, the enemycharacter is deemed to be eliminated. Note that in addition to the enemycharacter status data 22 f, the WRAM 22 has stored therein dataindicating the status of the player character. In addition to the datashown in FIG. 9, the WRAM 22 also has stored therein various types ofdata for use in the game process.

Next, a flow of the game process implemented by the game apparatus 1 isdescribed with reference to FIGS. 10 through 20. FIG. 10 is a flowchartshowing a flow of the game process implemented by the game apparatus 1.When the game apparatus 1 is turned on, the CPU core 21 of the gameapparatus 1 implements a startup program stored in a boot ROM (notshown) to initialize units in the game apparatus 1, e.g., the WRAM 22.Then, a game program stored in the cartridge 17 is read onto the WRAM22, and implementation of the game program is started. Consequently, agame image is generated in the first GPU 36, and then displayed on thefirst LCD 11, thereby starting a game. The game process shown in theflowchart of FIG. 10 is carried out after the game image is switched toa battle scene. Accordingly, the game process shown in the flowchart ofFIG. 10 is started after a battle between the player character and theenemy characters is started. Note that the descriptions of the gameprocess are omitted herein with respect to situations other than thebattle scene which are not directly related to an exemplary illustrativeembodiment.

Referring to FIG. 10, in step S41, an enemy character, the enemycharacter's characteristic parameters, and the player character'scharacteristic parameters are displayed on the display screen of thefirst LCD 11 (see FIG. 4B). In this case, the displayed characteristicparameters of the enemy character and the player character are HPs andMPs. In the following step S42, it is determined whether it is theplayer character's turn to attack. Note that a turn to attack isdetermined in accordance with a predetermined rule. Although this rulestipulates that the player character's turn to attack alternates withthe enemy character's turn to attack, any rule can be adopted.

If it is determined in step S42 not to be the player character's turn toattack, the procedure proceeds to step S43 where the enemy characterattacks the player character. Specifically, when the player character isattacked by the enemy character, values of characteristic parameters(i.e., HP and MP) of the player character are changed in accordance withthe enemy character's attack. Accordingly, the values of thecharacteristic parameters of the player character stored in the WRAM 22are updated. After the process of step S43, the procedure proceeds tostep S44.

Referring back to step S42, if it is determined to be the playercharacter's turn to attack, the player character attacks the enemycharacter in accordance with the processes of steps S44 through S46. Instep S44, an input detection process to the touch panel 13 is performed.In the input detection process to the touch panel 13, it is determinedwhether any input has been provided to the touch panel 13, and the inputcoordinate list 22 a is generated. The input detection process to thetouch panel 13 is described below with reference to FIGS. 11-13.

FIG. 11 is a flowchart showing a detailed flow of the process of stepS44 shown in FIG. 10. Firstly, in step S51, the input coordinate list 22a stored in the WRAM 22 is initialized. Specifically, a memory regionfor storing a predetermined number of coordinate values is reservedwithin the WRAM 22. At this point, a coordinate value, which indicates aposition where the player's input is provided, is not written in theinput coordinate list 22 a. In the following step S52, it is determinedwhether any input to the touch panel 13 has been detected. If the playerhas operated the touch panel 13 (e.g. the player has touched the touchpanel 13), an input to the touch panel 13 is detected and the procedureproceeds to step S53. On the other hand, if the player has not operatedthe touch panel 13, no input to the touch panel 13 is detected and theprocedure returns to step S52. That is, the process of step S52 isrepeatedly performed until the player operates the touch panel 13.

Processes of steps S53 through S57 are performed for detecting an inputposition on the touch panel 13. Through the processes of steps S53through S57, the input coordinate list 22 a is generated. The outline ofthe processes of steps S53 through S57 is described below with referenceto FIGS. 12 and 13.

FIG. 12 is a diagram schematically showing how an input to a touch panelis performed. In FIG. 12, the player is assumed to have performed aninput operation so as to draw an input trajectory, as indicated bybroken lines. In response to the input operation, the game apparatus 1detects a position on the touch panel where the player's input isprovided, at prescribed time intervals. Circles shown in FIG. 12indicate locations (detection points) at which the player's input to thetouch panel 13 has been detected.

In FIG. 12, a detection point p1 is detected before subsequent detectionpoints p2, p3, . . . are sequentially detected. Note that in FIG. 12,the y-axis indicates the vertical axis (a normal direction thereof isdirected downward to the bottom of FIG. 12), the x-axis indicates thehorizontal axis (a normal direction thereof is directed to the right ofFIG. 12), and the top left corner of the touch panel 13 is at theorigin. There are n detection points (where n is an arbitrary integer).A coordinate value of the detection point p1 is (80, 40), a coordinatevalue of the detection point p2 is (77, 42), and a coordinate value ofthe detection point p3 is (75, 45).

FIG. 13 shows an exemplary input coordinate list 22 a generated when theplayer's input is provided as shown in FIG. 12. As shown in FIG. 13, theinput coordinate list 22 a comprises detected coordinate values in theorder of detection. Specifically, the coordinate value (80, 40) at thedetection point p1 is listed first, the coordinate value (77, 42) at thedetection point p2 is listed second, and the coordinate value (75, 45)at the detection point p3 is listed third. In this manner, thecoordinate values at the detection points are written into the inputcoordinate list 22 a. Note that the exemplary input coordinate listshown in FIG. 13 comprises n coordinate values corresponding to thenumber of detection points.

Referring back to FIG. 12, the player's input to the touch panel 13 isnot detected after detection of an n'th detection point pn.Consequently, the input coordinate list 22 a having n coordinate valuesincluded therein is generated. The thus-generated input coordinate list22 a represents an input trajectory drawn by a continuous input to thetouch panel 13. The detailed descriptions of the processes of stepsS53-S57 are given below.

Referring back to FIG. 11, in step S53, the player's input to the touchpanel 13 is detected at prescribed time intervals. Specifically,coordinate values, which indicate positions on the touch panel 13 wherethe player's input is provided, are sequentially transmitted from thetouch panel 13 to the CPU core 21. In the following step S54, it isdetermined whether the latest coordinate value detected in step S53 isthe same as a previous coordinate value. If these two values aredetermined to be the same, the processes of steps S55 and S56 areskipped because they are not required to be performed, and the procedureproceeds to step S57.

Referring back to step S54, if it is determined that the latestcoordinate value detected in step S53 is not the same as the previouslycoordinate value, the procedure proceeds to step S55 where the latestcoordinate value is added to the input coordinate list 22 a so as tomaintain chronological order. That is, the latest coordinate valuedetected in step S53 is stored into the input coordinate list 22 a so asto follow the previous coordinate value as in the order they aredetected.

Following step S55, in step S56, the input trajectory representation 33(FIG. 4A) is displayed at a position on the display screen whichcorresponds to a position represented by coordinate values detected instep S53. Specifically, a line extending between a location indicated bythe latest coordinate value detected in step S53 and the previouscoordinate value is displayed on the first LCD 11. After the process ofstep S56, the procedure proceeds to step S57.

In step S57, it is determined whether the player's input to the touchpanel 13 is continued, (e.g. whether the player's finger remains on thetouchpanel 13). In step S57, if the player's finger remains on the touchpanel 13, the input to the touch panel 13 is detected, and therefore itis determined that the player's input to the touch panel 13 iscontinued. In this case, the procedure returns to step S53. Accordingly,while the player's input to the touch panel 13 is continued, theprocesses of steps S53 through S57 are repeatedly performed. Note thatin step S57, if the player's finger is out of contact with the touchpanel 13, no input to the touch panel 13 is detected. Accordingly, it isdetermined that the player's input to the touch panel 13 is notcontinued. In this case, the CPU core 21 terminates the input detectionprocess to the touch panel shown in FIG. 11.

Referring back to FIG. 10, following step S44, an attack detailsdetermination process is performed in step S45. In the attack detailsdetermination process, the style of an attack, an attack target, and anattack power are determined based on the shape, size, and position ofthe input trajectory. The detailed descriptions of the attack detailsdetermination process are provided below with reference to FIGS. 14through 18.

FIG. 14 is a flowchart showing the details of a flow of the process ofstep S45 shown in FIG. 10. In FIG. 14, the processes of steps S61 andS62 are performed for simplifying information comprising the inputcoordinate list 22 a generated in step S44. Since the informationcomprising the input coordinate list 22 a is a set of coordinate values,if the information is not suitably processed, it is difficult toidentify the shape of the input trajectory. The processes of steps S61and S62 are intended to facilitate easy identification of the shape ofthe input trajectory by processing the information comprising the inputcoordinate list 22 a. The outline of the processes of steps S61 and S62is now described.

FIGS. 15A through 15C are diagrams used for explaining a process forsimplifying the input coordinate list 22 a. FIG. 15A is a diagramschematically showing a coordinate value group comprising the inputcoordinate list 22 a. As described above, the input coordinate list 22 acomprises coordinate values indicating positions on the touch panel 13which are detected at predetermined time intervals. In FIG. 15A,detection points p1, p2, and p3 each correspond to a coordinate valuecomprising the input coordinate list 22 a. In the processes of steps S61and S62, the vector data list 22 b is initially generated based on theinput coordinate list 22 a.

FIG. 15B is a diagram schematically showing the vector data list 22 b.The vector data list 22 b comprises a plurality of pieces of vector dataeach indicating a vector between adjacent detection points. For example,a vector v1 shown in FIG. 15B lies between the detection points p1 andp2. Note that each vector is obtained so as to point in a direction ofthe player's input operation, (e.g. the vector is directed from apreviously detected point to a later detected point). The vector datalist 22 b is generated by obtaining all of the plurality of pieces ofvector data between adjacent detection points (see step S61 which willbe described later). Note that eight directions are represented by theplurality of pieces of vector data comprising the vector data list 22 b.For example, although there might be a slight difference between adirection from the detection point p1 to the detection point p2 and adirection from the detection point p2 to the detection point p3, thevectors v1 and v2 are treated as the same direction because informationrelated to directions are simplified when generating the vector data.

Next, in the processes of steps S61 and S62, the input trajectory data22 c is generated based on the vector data list 22 b. Specifically,sequential pieces of vector data indicating the same direction andcomprising the vector data list 22 b are combined into one piece ofvector data. FIG. 15C is a diagram schematically showing the inputtrajectory data 22 c. Since vectors v1 through v5 shown in FIG. 15B havethe same direction as each other, they are combined into one piece ofvector data. As a result, in FIG. 15C, one side of a triangular inputtrajectory is represented by one vector v′1. Similarly, in other sidesof the triangular trajectory, vectors with the same direction arecombined into one vector. As a result, the input trajectory data 22 crepresents an input trajectory with three pieces of vector data.Accordingly, based on the input trajectory data 22 c including the threepieces of vector data, it can be readily recognized that the inputtrajectory shown in FIGS. 15A through 15C have a triangular shape. Inthis manner, through the processes of steps S61 and S62, it is possibleto considerably simplify information representing the input trajectory,thereby making it possible to facilitate identification of the shape ofthe input trajectory.

Note that if the time intervals of detecting an input to the touch panel13 are relatively long, or if the speed at which the player moveshis/her finger on the touch panel 13 is relatively fast, there is apossibility that a position of a vertex of the input trajectory mightnot be detected. In such a case, as shown in FIG. 16A, vector data v,which is inconsistent with an actual input trajectory (indicated bydotted lines), is obtained. Consequently, the input trajectory data 22 ccomprises four pieces of vector data (see FIG. 16B), and therefore theinput trajectory might be misrecognized as a rectangle, for example. Inorder to prevent this, in addition to the processes of steps S61 andS62, a correction process may be performed for deleting vector data ofless than a prescribed length from the vector data stored in the inputtrajectory data 22 c. This deletes a piece of vector data, which isgenerated when a position of a vertex of the input trajectory is notdetected and is inconsistent with an actual input trajectory, therebypreventing misrecognition of the shape of the input trajectory.

Referring back to FIG. 14, the detailed descriptions of the processes ofsteps S61 and S62 are provided below. In step S61, a piece of vectordata indicating a vector between adjacent coordinate values is obtainedbased on the coordinate value group comprising the input coordinate list22 a (see FIG. 15B). The vector data list 22 b is generated by obtainingeach piece of vector data between adjacent detection points. Note that apiece of vector data between an i'th input coordinate value (where i isa natural number equal to or less than n−1) and an i+1'th inputcoordinate value is listed i'th in the vector data list 22 b.

FIGS. 17A and 17B are diagrams used for explaining the vector data list22 b. Specifically, FIG. 17A shows an exemplary vector data list 22 bobtained by performing the process of step S45. As described above, inthe present exemplary illustrative embodiment, directions of vectors arerepresented with eight directions. Specifically, the directions of thevectors are represented using direction codes 0 through 7 shown in FIG.17B. The direction of a vector can be obtained based on coordinatevalues of adjacent detection points as described below. Consider a casewhere a coordinate value of a previously obtained detection point isrepresented by (x1, y1), a coordinate value of a later obtaineddetection point is represented by (x2, y2), Rx=x2−x1, and Ry=y2−y1. IfRy<0 and |Ry|>2|Rx|, the direction code is 0 (an upward direction); ifRx>0, Ry<0, and 2|Rx|>=|Ry|>=|Rx|/2, the direction code is 1 (an upperright direction); if Rx>0 and |Rx|>2|Ry|, the direction code is 2 (aright direction); if Rx>0, Ry>0, and 2|Rx|>=|Ry|>=|Rx|/2, the directioncode is 3 (a lower right direction); if Ry>0 and |Ry|>2|Rx|, thedirection code is 4 (a downward direction); if Rx<0, Ry>0, and2Rx|>=|Ry|>=|Rx|/2, the direction code is 5 (a lower left direction); ifRx<0 and |Rx|>2|Ry|, the direction code is 6 (a left direction); ifRx<0, Ry<0, and 2|Rx|>=|Ry|>=|Rx|/2, the direction code is 7 (an upperleft direction). In this manner, the vector data can be represented withthe above eight directions. This simplifies the shape of the inputtrajectory, and therefore it is possible to simplify a process foridentifying the shape of the input trajectory (which will be describedlater in relation to step S64). Note that the top left corner of thedisplay screen is at the origin, and a coordinate value increases as adistance from the origin increases on a side of the display screen.

Referring back to FIG. 14, following step S61, the process of step S62is performed. In step S62, the input trajectory data 22 c is generatedbased on the vector data list 22 b. Specifically, the input trajectorydata 22 c is generated by combining sequential pieces of vector dataindicating the same direction and comprising the vector data list 22 b.The sequential pieces of vector data indicating the same direction areshown in FIG. 17A as, for example, four pieces of vector datarespectively specified by data nos. 1 through 4. These four pieces ofvector data have the same direction code, and therefore can be combinedinto one piece of vector data. The distance of the combined vector datais equal to the sum of the distances of the four pieces of vector data.The direction of the combined vector data is naturally the same as thedirection of the four pieces of vector data. As for vector dataspecified by data nos. 5 and greater, pieces of vector data indicatingthe same direction are similarly combined into one piece of vector data.Thus, the input trajectory data 22 c as shown in FIG. 18 is obtained. InFIG. 18, vector data specified by data no. 1 (distance: 10; direction:5) is obtained by combining the pieces of vector data specified by datanos. 1 through 4 comprising the vector data list 22 b shown in FIG. 17A.

Following step S62, in step S63, the reference graphics database 22 d isread from the WRAM 22. FIG. 19 is a diagram showing an exemplaryreference graphics database 22 d. As shown in FIG. 19, in the referencegraphics database 22 d, shapes of reference graphics and referencegraphics data representing the shapes are associated with each other.Similar to the vector data list 22 b and the input trajectory data 22 c,apiece of the reference graphics data representing the shapes of thereference graphics comprises vector data. In FIG. 19, the referencegraphics data are associated with a rectangle, a circle, and a triangle,for example. In the present exemplary illustrative embodiment, eightdirections can be represented by the vector data, and therefore thereference graphics data associated with the circle actually representsan octagon. Moreover, all sides of a reference graphic have a length of1.

In step S64, a piece of reference graphics data, which represents ashape most analogous to a shape represented by the input trajectory datagenerated in step S62, is selected from the reference graphics data readin step S63. The shape represented by the reference graphics dataselected in step S64 is identified as the shape of the input trajectory.The details of the process of step S64 are as follows.

In step S64, similarity transformation is performed on the inputtrajectory data. In the similarity transformation, a graphic representedby the input trajectory data is enlarged or reduced so as to be almostequal in size to the reference graphic. In the present exemplaryillustrative embodiment, a magnification for enlargement or reduction isdetermined based on a piece of vector data indicating a minimum distance(hereinafter, referred to as “vector data A”) and a piece of vector dataindicating a maximum distance (hereinafter, referred to as “vector dataB”). Specifically, the magnification for enlargement or reduction isdetermined by the following exemplary formula: (the magnification forenlargement or reduction)=(a distance indicated by the vector data A)/(adistance indicated by the vector data B). For example, consider a casewhere the similarity transformation is performed on the input trajectorydata shown in FIG. 18 for comparison with the reference graphics datashown in FIG. 19. In this case, a minimum distance of vector datacomprising the reference graphic data is 1, and a minimum distance ofvector data comprising the input trajectory data is 10. Accordingly, theobtained magnification for enlargement or reduction is 1/10. Therefore,the vector data comprising the input trajectory data is reduced to 1/10in order to obtain a graphic represented by the input trajectory datawhich is almost equal in size to the reference graphic.

After the similarity transformation is performed on the input trajectorydata, the input trajectory data is compared with the reference graphicsdata. For example, the comparison is performed using a dissimilarityvalue. The dissimilarity value indicates a degree of difference betweenthe shape represented by the input trajectory data subjected to thesimilarity transformation and the shape represented by the referencegraphics data. For example, the dissimilarity value is obtained by thefollowing expression:

(the dissimilarity value)=(a difference in number of pieces of vectordata)×10+(the number of different directions)×2+(sum of differencesbetween distances)×1

In the above expression, the difference in number of pieces of vectordata corresponds to a difference between the number of pieces of vectordata comprising the input trajectory data and the number of pieces ofvector data comprising the reference graphics data. For example, thenumber of pieces of vector data comprising the input trajectory datashown in FIG. 18 is 3, and the number of pieces of vector datacomprising the reference graphics data A (rectangle) shown in FIG. 19 is4. Accordingly, in this case, the difference in number of pieces ofvector data is 1.

The number of different directions corresponds to the number ofdifferences between directions indicated by the vector data comprisingthe input trajectory data and directions indicated by the vector datacomprising the reference graphics data. For example, comparing the inputtrajectory data shown in FIG. 18 and the reference graphics data A(rectangle) shown in FIG. 19, it is found that only vector dataindicating a vector directed to the right (i.e., a piece of vector dataspecified by data no. 2 in FIG. 18 and a piece of vector data specifiedby data no. 2 in the reference graphics data A (rectangle) in FIG. 19)are equal in direction to each other. No vector data comprising thereference graphics data A shown in FIG. 19 indicates the same directionas the directions indicated by two other pieces of vector datacomprising the input trajectory data, and therefore the difference innumber of directions is 2.

The sum of differences between distances corresponds to a sum ofdifferences in distance between vector data comprising the inputtrajectory data and vector data comprising the reference graphics data.Specifically, a difference between two pieces of vector data specifiedby the same data number are obtained with respect to the vector datacomprising the input trajectory data 22 c and the reference graphicsdata. Further, the sum of differences obtained with respect to all datanumbers is calculated. For example, in the case of comparing the inputtrajectory data (subjected to the similarity transformation) shown inFIG. 18 to the reference graphics data A (rectangle) shown in FIG. 19,distances indicated by the vector data are all 1, and therefore the sumof differences of distances is 0.

In step S64, each piece of the reference graphics data is compared tothe input trajectory data. Consequently, a piece of the referencegraphics data having a minimum dissimilarity value is selected asrepresenting a shape, which is most analogous to the shape representedby the input trajectory data. Note that when the input trajectory datashown in FIG. 18 is compared to the reference graphics data A through Cshown in FIG. 19, the reference graphics data C (triangle) has adissimilarity value of 0, and therefore the reference graphics data C(triangle) is selected as representing a shape which is most analogousto the shape represented by the input trajectory data. Thus, the shapeof the input trajectory is identified to be a triangle.

Following step S64, in step S65, the style of attack corresponding tothe shape of the input trajectory is determined based on the selectedpiece of reference graphics data and the attack determination table.FIG. 20 shows an exemplary attack determination table. As shown in FIG.20, in the attack determination table, shapes of input trajectories areassociated with styles of attack. In step S65, the style of attackcorresponding to the shape of the input trajectory is determined so asto correspond to the shape of the input trajectory specified in stepS64.

Following step S65, in step S66, the size of the input trajectory isidentified. Note that the size of the input trajectory is representedrelative to the size of the reference graphic. Specifically, the size ofthe input trajectory is expressed by a magnification relative to thereference graphic. For example, an input trajectory represented by theinput trajectory data shown in FIG. 18 is ten times larger than thereference graphic represented by the reference graphics data C(triangle) shown in FIG. 19. The magnification used for expressing thesize of the input trajectory can be obtained as a reciprocal of amagnification used in the above-described similarity transformation(step S64).

Following step S66, in step S67, an attack power is determined based onthe size of the input trajectory identified in step S66. The attackpower is represented by a numerical value associated with a degree ofdamage to be caused to an enemy character. Final damage to be caused tothe enemy character is determined by adjusting the attack power in stepS75 which will be described later. Specifically, a value of the attackpower is determined with reference to the attack determination tableshown in FIG. 20. In the attack determination table of FIG. 20, basicdamage and a magnification corresponding to the size of the inputtrajectory are associated for each style of attack. The product of thebasic damage and the magnification corresponds to the value of theattack power. For example, when the style of attack is an attack by firemagic and the size of the input trajectory is three times the inputtrajectory, the value of the attack power is obtained such as 30 (basicdamage)×0.5=15. After the process of step S67, the procedure of theflowchart shown in FIG. 14 is terminated.

Referring back to FIG. 10, following step S45, an attack process of stepS46 is performed. The attack process is performed to cause damage to theenemy character based on, for example, the attack power determined instep S45. The details of the attack process are described below withreference to FIGS. 20 through 22.

FIG. 21 is a flowchart showing the details of a flow of the process ofstep S46 shown in FIG. 10. In step S71, of enemy characters displayed ina game image, an enemy character in an area enclosed by the inputtrajectory is identified. The identified enemy character is targeted forattack by the player character. Note that an enemy character partiallylying in the area may or may not be targeted for attack. In thefollowing step S72, it is determined whether any enemy character hasbeen identified in step S71. If no enemy character has been identifiedin step S71 (e.g. the enemy character is not present in the area), theprocedure proceeds to step S73. In this case, there is no enemycharacter targeted for attack, in the area, an effect representation ispresented to show the failure of the attack, and the process shown inFIG. 21 is terminated.

Alternatively, if it is determined in step S72 that there has been anenemy character identified in step S71, the processes of steps S74through S77 are performed. In the processes of steps S74 through S77, adegree of damage to be caused to the enemy character targeted for attackis determined. Firstly, in step S74, an attribute of the enemy characteridentified in step S71 is identified. The process of step S74 isperformed based on the enemy character status data 22 f. FIG. 22 is adiagram showing an example of the enemy character status data. As shownin FIG. 22, the enemy character status data 22 f comprises attributedata, HP, and MP for each enemy character. In step S74, the attributedata of the enemy character identified at step S71 is identified asattributed character attribute data specified in step S71.

Following step S74, in step S75, damage to be caused to the enemycharacter is determined based on the attribute data identified in stepS74. Specifically, in step S75, the damage is determined based on theattack power determined in step S44 and the attribute data read in stepS74. Note that the above determination process is provided withreference to the attack determination table shown in FIG. 20. As shownin FIG. 20, in the attack determination table, a magnification frombasic damage is set for each set of a style of attack and enemycharacter attributes. In the process of step S75, a magnificationcorresponding to the enemy character's attribute is determined based onthe attribute identified in step S74 and the style of attack determinedin step S65. In the example of FIG. 20, if the style of attack is anattack by water magic and the attribute of the enemy character is a fireattribute, the magnification is determined to be twice the degree of thebasic damage. Then, the attack power determined in step S44 ismultiplied by the determined magnification, thereby determining thedegree of final damage to be caused to the enemy character. In the aboveexample, if the attack power is 15, the degree of final damage to becaused to the enemy character is determined by 15×2=30.

Following step S75, in step S76, an effect representation correspondingto the style of attack by the player character is displayed on thedisplay screen (see FIGS. 8A and 8B). Image data for the effectrepresentation is prestored for each attack style. In the following stepS77, the enemy character's characteristic parameter (specifically, HP)is changed in accordance with the degree of the damage determined instep S75. Specifically, the CPU core 21 reduces the HP comprising theenemy character status data 22 f stored in the WRAM 22 by the degree ofthe damage determined in step S75, thereby updating the HP. Note thatthe enemy character having HP targeted for updating is present in thearea enclosed by the input trajectory (e.g. the enemy character isidentified in step S74). After the process of step S77, the procedure ofthe flowchart shown in FIG. 21 is terminated.

Referring back to FIG. 10, after the process of step S46, the process ofstep S47 is performed. In step S47, it is determined whether a battle iscompleted. This determination is made based on, for example, whether theplayer character's HP or all enemy characters' HPs is/are reduced tozero. Specifically, if the player character's HP or all enemycharacters' HPs is/are reduced to zero, it is determined that the battleis completed, and the battle process shown in FIG. 10 is terminated. Onthe other hand, if the player character's HP and any one enemycharacter's HP are not reduced to zero, it is determined that the battleis not completed, and the procedure returns to step S41. In this case,the processes of steps S41 through S47 are repeatedly performed untilthe battle is deemed to be completed. Thus, the description of the gameprocess according to the present exemplary illustrative embodiment hasbeen completed.

As described above, in a touch-panel type game apparatus according tothe present exemplary illustrative embodiment, the style of attack canbe changed in accordance with the shape of an input trajectory drawn onthe display screen by the player's input. Accordingly, a game operationcan be performed in various manners, and various styles of attack can beperformed in a game. Moreover, it is possible to change a degree of anattack or a range targeted for attack in accordance with the size of theinput trajectory or a range enclosed by the input trajectory, andtherefore it is possible to diversify the pattern of attack.

Although the present exemplary illustrative embodiment has beendescribed above with respect to operations of attacking enemy charactersin battle scenes of a RPG, the present invention is not limited to suchoperations. For example, an exemplary illustrative embodiment isadvantageous for use in operations of recovering or protecting theplayer character. Specifically, it is conceivable that the type of arecovery operation (e.g., an operation of recovering HP, an operation ofallowing the player character to recover from a poisoned state, etc.) ischanged in accordance with the shape of the input trajectory, and adegree of recovery (e.g., the amount of HP to be recovered) is changedin accordance with the size of the input trajectory.

Further, the present exemplary illustrative embodiment has beendescribed above with respect to a case where an enemy character to beattacked is present in an area enclosed by the input trajectory.However, the present invention is not limited to this so long as theenemy character to be attacked is determined based on an area enclosedby the input trajectory. For example, only an enemy character, which isin contact with the input trajectory or located outside the areaenclosed by the input trajectory, may be targeted for attack (e.g. theenemy character present in the area enclosed by the input trajectory isnot attacked).

Furthermore, the present exemplary illustrative embodiment has beendescribed above with respect to a case where the reference graphic has aclosed shape, such as a circle, a triangle, and a rectangle. However,the reference graphic does not have to have a closed shape. For example,the reference graphic may have an arc shape as shown in FIG. 23 or aspiral shape as shown in FIG. 24. Alternatively, the reference graphicmay have an undulating shape as shown in FIG. 25. Note that in the casewhere the reference graphic does not have a closed shape, an area fordetermining a target for attack (in the above exemplary illustrativeembodiment, the area enclosed by the input trajectory) cannot bedetermined based on the shape of the reference graphic. Accordingly, inthis case, an area corresponding to a reference graphic and targeted forattack may be previously determined for each possible shape of thereference graphic. For example, in the shapes shown in FIGS. 23 through25, a hatched portion may be determined as the area targeted for attack.

Further still, the reference graphic does not have to have a shape whichcan be drawn with one stroke. For example, the reference graphic mayhave a shape made of a combination of a circle and straight lines asshown in FIG. 26. Note that in the case where the reference graphic hasthe shape shown in FIG. 26, if a trajectory which can be drawn by onecontinuous input operation is considered to be a single input trajectory(see step S57 of FIG. 11), it is not possible to draw the referencegraphic because the shape shown in FIG. 26 cannot be drawn with onestroke.

Accordingly, in this case, a trajectory inputted within a predeterminedtime period can be considered to be a single input trajectory.Specifically, in step S57 of FIG. 11, it may be determined whether thepredetermined time period has elapsed after detection of an input instep S52.

In another exemplary illustrative embodiment, the damage to be caused toan enemy character may be changed in accordance with the number of enemycharacters present in an area enclosed by the input trajectory. Forexample, if there is only one enemy character present in the area, thedamage to be caused to that one enemy character may be greater thandamage per enemy character for two enemy characters.

Note that although an exemplary liquid crystal display section forsimultaneously displaying two separate images has been described abovewith respect to a case where the two LCDs 11 and 12 are arranged so asto be physically separated in a vertical direction, the LCDs 11 and 12may be arranged side by side in a horizontal direction without using theupper housing 18 b. In order to arrange the LCDs 11 and 12 side by sidein a horizontal direction, as shown in FIG. 27, a housing 18 c having awide rectangular shape may be provided so as to accommodate the LCDs 11and 12 therein. In such a case, it is preferred that the LCD 12 havingthe touch panel 13 mounted thereon is located to the right of the LCD 11because users frequently are right-handed. However, the LCDs 11 and 12may be arranged the other way around in a portable game apparatus for aleft-handed user.

Further, instead of arranging the LCDs 11 and 12 so as to be physicallyseparated in a vertical direction, an LCD 11 a having a length twice thelength of the LCD 11 and the same width as that of the LCD 11 as shownin FIG. 28 (i.e., the LCD 11 a has physically one display screen havinga size twice the size of the display screen of the LCD 11 in a verticaldirection), may be provided so as to separately display two game imageson the display screen (such that the two game images are adjacent toeach other without a gap therebetween in a vertical direction).Alternatively, an LCD 11 b having a width twice the width of the LCD 11and the same length as that of the LCD 11 as shown in FIG. 29 (i.e., theLCD 11 b has physically one display screen having a size twice the sizeof the display screen of the LCD 11 in a horizontal direction), may beprovided so as to separately display two game images on the displayscreen (such that the two game images are adjacent to each other withouta gap therebetween in a horizontal direction).

In the examples of FIGS. 28 and 29, a plurality of game images can beseparately displayed on one display screen.

Although the present invention has been described and illustrated indetail, it is clearly understood that the same is by way of illustrationand example only and is not to be taken by way of limitation, the spiritand scope of the present invention being limited only by the terms ofthe appended claims.

1. A computer-readable storage medium having a game program storedtherein, the game program causing a computer of a game apparatus, whichgenerates a game image for display on a display screen, to implement amethod comprising: a game image display control step of allowing a gameimage comprising one or more game characters to be displayed on thedisplay screen; a coordinate detection step of detecting a coordinatevalue at specified time intervals, the coordinate value indicating aposition on the display screen which is pointed to by a pointing device;a shape identification step of identifying a graphical shape of an inputtrajectory represented by a coordinate value group detected by thecoordinate detection step; a size calculation step of calculating a sizeof the graphical shape of the input trajectory represented by thecoordinate value group detected by the coordinate detection step; abasic condition determination step of determining an attack style forchanging respective characteristic parameters of at least one attackedgame character based on the graphical shape identified by the shapeidentification step, each characteristic parameter indicating acharacteristic of the corresponding attacked game character; aneffectiveness determination step of determining an effectiveness of theattack style on the at least one attacked game character based on thesize calculated by the size calculating step; and a characteristicparameter change step of changing the characteristic parameter of the atleast one attacked game character based on the attack style determinedby the condition determination step and the attack effectivenessdetermined by the effectiveness determination step.
 2. The storagemedium according to claim 1, wherein the method further comprises acharacter selection step of selecting the at least one attacked gamecharacter from among the one or more game characters contained in thegame image, and wherein the characteristic parameter change step changesonly the characteristic parameter of the at least one attacked gamecharacter selected by the character selection step.
 3. The storagemedium according to claim 2, wherein the characteristic parameter changestep changes a degree of change in the characteristic parameter inaccordance with a number of the at least one game character selected bythe character selection step.
 4. The storage medium according to claim1, wherein the method further comprises a change representation additionstep of, after the graphical shape of the input trajectory is identifiedby the shape identification step, changing the game image in a differentmanner in accordance with a type of the basic condition determined bythe graphical shape of the input trajectory.
 5. The storage mediumaccording to claim 1, wherein the method further comprises a trajectorydisplay control step of displaying the input trajectory in a position onthe display screen which corresponds to the coordinate value detected bythe coordinate detection step.
 6. The storage medium according to claim1, wherein from among a plurality of pieces of reference graphics datastored in the game apparatus and indicating a type of the basiccondition, the shape identification step selects a piece of referencegraphics data, which indicates a shape most analogous to a shaperepresented by the coordinate value group, and the shape identificationstep determines the shape represented by the selected piece of referencegraphics data as the graphical shape of the input trajectory.
 7. Thestorage medium according to claim 6, wherein the method furthercomprises: a vector data group calculation step of calculating a vectordata group indicating a distance and a direction between sequentialcoordinate values based on the coordinate value group detected by thecoordinate detection step; and a correction step of correcting aplurality of sequential pieces of vector data indicating a samedirection and contained in the vector data group, so as to berepresented as a piece of vector data, and wherein the shapeidentification step selects a piece of reference graphics dataindicating a shape most analogous to a shape of the vector data groupcorrected by the correction step.
 8. A game apparatus comprising: thestorage medium of claim 1; and a program implementing section forimplementing a game program stored in the storage medium.
 9. Acomputer-readable storage medium having a game program stored therein,the game program causing a computer of a game apparatus, which generatesa game image for display on a display screen, to implement a methodcomprising: a game image display control step of allowing a game imagecomprising game characters to be displayed on the display screen; acoordinate detection step of detecting a coordinate value at specifiedtime intervals, the coordinate value indicating a position on thedisplay screen which is pointed to by a pointing device; a shapeidentification step of identifying a graphical shape of an inputtrajectory represented by a coordinate value group detected by thecoordinate detection step; a character selection step of selecting forattack at least one game character having a characteristic parameter,which indicates a characteristic of the game character and is requiredto be changed, from among the game characters contained in the gameimage based on an area on the display screen which is defined by theinput trajectory; a basic condition determination step of determining anattack style for changing the characteristic parameter, which indicatesthe characteristic of the attacked game character, based on thegraphical shape identified by the shape identification step; and acharacteristic parameter change step of changing the characteristicparameter of the at least one attacked game character selected by thecharacter selection step, based on the attack style determined by thecondition determination step.
 10. The storage medium according to claim9, wherein the method further comprises: a size calculation step ofcalculating a size of the graphical shape of the input trajectoryrepresented by the coordinate value group detected by the coordinatedetection step; and an effectiveness determination step of determiningan effectiveness of the attack style on the at least one attacked gamecharacter based on the size calculated by the size calculating step, andwherein the characteristic parameter change step changes thecharacteristic parameter of the at least one game character based on theeffectiveness of the attack style determined by the effectivenessdetermination step.
 11. The storage medium according to claim 9, whereinthe characteristic parameter change step changes a degree of change inthe characteristic parameter in accordance with a number of the at leastone game character selected by the character selection step.
 12. Thestorage medium according to claim 9, wherein the method furthercomprises a change representation addition step for, after the graphicalshape of the input trajectory is identified by the shape identificationstep, changing the game image in a different manner in accordance with atype of the basic condition determined by the graphical shape of theinput trajectory.
 13. The storage medium according to claim 9, whereinthe method further comprises a trajectory display control step ofdisplaying the input trajectory in a position on the display screenwhich corresponds to the coordinate value detected by the coordinatedetection step.
 14. The storage medium according to claim 9, whereinfrom among a plurality of pieces of reference graphics data stored inthe game apparatus and indicating a type of the basic condition, theshape identification step selects a piece of reference graphics data,which indicates a shape most analogous to a shape represented by thecoordinate value group, and the shape identification step determines theshape represented by the selected piece of reference graphics data asthe graphical shape of the input trajectory.
 15. The storage mediumaccording to claim 14, wherein the method further comprises: a vectordata group calculation step of calculating a vector data groupindicating a distance and a direction between sequential coordinatevalues based on the coordinate value group detected by the coordinatedetection step; and a correction step of correcting a plurality ofsequential pieces of vector data indicating a same direction andcontained in the vector data group, so as to be represented as a pieceof vector data, and wherein the shape identification step selects apiece of reference graphics data indicating a shape most analogous to ashape of the vector data group corrected by the correction step.
 16. Agame apparatus comprising: the storage medium of claim 9; and a programimplementing section for implementing a game program stored in thestorage medium.
 17. A method for changing a game parameter, the methodbeing implemented by a computer of a game apparatus, which generates agame image for display on a display screen, the method comprising: agame image display control step of allowing a game image comprising gamecharacters to be displayed on the display screen; a coordinate detectionstep of detecting a coordinate value at specified time intervals, thecoordinate value indicating a position on the display screen which ispointed to by a pointing device; a shape identification step ofidentifying a graphical shape of an input trajectory represented by acoordinate value group detected by the coordinate detection step; a sizecalculation step of calculating a size of the graphical shape of theinput trajectory represented by the coordinate value group detected bythe coordinate detection step; a basic condition determination step ofdetermining an attack style for changing a characteristic parameter ofan attacked game character, which characteristic parameter indicates acharacteristic of the attacked game character, based on the graphicalshape identified by the shape identification step; an effectivenessdetermination step of determining an effectiveness of the attack styleon the attacked game character based on the size calculated by the sizecalculating step; and a characteristic parameter change step of changingthe characteristic parameter of the attacked game character based on theattack style determined by the condition determination step and theeffectiveness of the attack style determined by the effectivenessdetermination step.
 18. A method for changing a game parameter, themethod being implemented by a computer of a game apparatus, whichgenerates a game image for display on a display screen, the methodcomprising: a game image display control step of allowing a game imagecomprising game characters to be displayed on the display screen; acoordinate detection step of detecting a coordinate value at specifiedtime intervals, the coordinate value indicating a position on thedisplay screen which is pointed to by a pointing device; a shapeidentification step of identifying a graphical shape of an inputtrajectory represented by a coordinate value group detected by thecoordinate detection step; a character selection step of selecting forattack at least one game character having a characteristic parameter,which indicates a characteristic of the attacked game character and isrequired to be changed, from among the game characters based on an areaon the display screen which is defined by the input trajectory; a basiccondition determination step of determining an attack style for changingthe characteristic parameter, which indicates the characteristic of theattacked game character, based on the graphical shape identifiedby theshape identification step; and a characteristic parameter change step ofchanging the characteristic parameter of the game character selected forattack by the character selection step, based on the attack styledetermined by the condition determination step.
 19. A computer-readablestorage medium having a game program stored therein, the game programcausing a processor of a game apparatus, which generates a game imagefor display on a display screen, to implement a method comprising:determining a size and a shape of an attack input supplied to the gameapparatus; and changing one or more characteristics of an attacked gamecharacter based on one or both of the size and shape of the suppliedattack input.
 20. The computer-readable storage medium according toclaim 19, wherein the input comprises an input drawn around the attackedgame character.
 21. The computer-readable storage medium according toclaim 19, wherein the input comprises an input drawn to touch theattacked game character.
 22. The computer-readable storage mediumaccording to claim 19, wherein the one or more characteristics comprisehit points (HP) of the attacked game character.
 23. Thecomputer-readable storage medium according to claim 19, wherein the oneor more characteristics comprise magic points (MP) of the attacked gamecharacter.
 24. The computer-readable storage medium according to claim19, wherein the shape of the attack input is determined by comparison ofthe attack input with a plurality of pre-stored shapes.
 25. Thecomputer-readable storage medium according to claim 19, wherein theshape of the attack input is determined using vector data generated fromthe attack input.